1. Field of the Invention
The present invention relates to a transfer needle assembly. The transfer needle assembly of the present invention eliminates problems such as the contamination of the tip of a needle before use and an injury by the tip of a needle and the leakage of a liquid when in use.
2. Description of the Related Art
For the preparation of a component liquid to be applied to a living body and mixed and injected at a medical facility or self-injected for home medical treatment, a dried medicine contained in a vial is dissolved, prepared and then transferred to a syringe to be used. A syringe with a needle or a tool having a hollow puncture needle at both ends, called a “double-ended needle”, has been used for these operations. When the syringe with a needle is used, a rubber stopper in the mouth portion of a solution container is pricked with the needle to collect a predetermined amount of the solution into the syringe and then a rubber stopper in the mouth portion of a vial is pricked with the needle to inject the solution into the vial. Then the vial is shaken to dissolve the medicine and the rubber stopper is pricked with the needle again to collect a predetermined amount of the medicinal liquid into the syringe. Further, when the double-ended needle is used, the rubber stopper of a vial filled with a medicine and the rubber stopper of a solution container are pricked with the puncture needles at both ends of the double-ended needle to provide communication between them, the solution is transferred to the vial to dissolve the medicine, the solution container and the double-ended needle are removed from the vial, and the rubber stopper of the vial is pricked with the needle likewise to collect a predetermined amount of the medicinal liquid into the syringe.
These prior art techniques involve a problem in that when the operation of dissolving a medicine is carried out using the syringe with a needle, the operation is complicated, the tip of the needle may become contaminated before use as the needle is exposed, and a patient or the like may be injured by the tip of the needle when in use. Further, when the double-ended needle is used and the needle is pulled out or a predetermined amount of the medicinal liquid is collected into the syringe, a patient or the like may be injured by the tip of the needle and the tip of the needle may be contaminated before the collection of the medicinal liquid because the tip of the needle is exposed the same as with the syringe with a needle. To solve the above problems, there is proposed an admixture injection adaptor which enables the injection and collection of a medicinal liquid during a dissolution operation (see Japanese laid open publication No. JP 7-213585).
In the admixture injection adaptor of the above JP 2002-360593 A, a hollow puncture needle and a pipe-shaped tip fitting part are set on opposite sides on the axis of a disc hub, respectively, and on the outer edge of the hub, tubular skirts concentrically extending over the puncture needle and the tip fitting part are constructed. The adaptor is convenient when it is used to transfer a medicinal liquid in a vial to a syringe after a dried medicine in the vial is dissolved to prepare the medicinal liquid because contamination of the tip of the needle or an injury by the needle is avoided. However, the length of the skirt is limited to prevent the end of the skirt from contacting with the shoulder of the vial when the vial is pricked with the needle, whereby the vial cannot be fitted straight, thereby forming a gap between the rubber stopper of the vial and the needle and thereby causing leakage of the medicinal liquid during the dissolution operation.
The present invention has been made in view of the above circumstances, and it is, therefore, an object of the present invention to provide a transfer needle assembly with which the dissolution operation can be carried out easily; contamination of the tip of the needle and injury by the tip of the needle can be avoided; and leakage of a liquid during the dissolution operation can be prevented.